Magnetic moment of 181Ta

Abstract

The nuclear magnetic moment of 181Ta is measured by NMR of a tantalum solution. For tantalum dissolved in HF/HNO3 broad lines arising from 181Ta nuclei in TaF6− complexes are observed at room temperature. A study of linewidth vs temperature shows motional narrowing of the quadrupole broadened line with increasing temperature. Applying the quadrupolar correction, we obtain a nuclear gyromagnetic ratio for 181Ta of 2π(0.5098 ± 0.0002) × 103 sec−1 G−1 and an uncorrected nuclear moment of 2.342 ± 0.001 nm. The chemical shift correction gives 2π(0.5097 ± 0.0002) × 103 sec−1 G−1 for the nuclear gyromagnetic ratio. Correcting the nuclear moment for core diamagnetism, we get 2.361 ± 0.010 nm.